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Genetic diversity and spatial genetic structure of Calophyllum brasiliense Camb. (Clusiaceae) in a swampy forest

The areas of occurrence of swampy forests have been altered and restricted due to destruction and fragmentation processes, with consequent reduction of their population size. Calophyllum brasiliense Camb. is an abundant tree species in Riparian environments for its preference for colonizing high water saturation soils, being considered specialist in habitat. Besides the ecological consequences, such as mortality and low recruitment, genetic variability loss can occur, compromising the viability of the species in the place. Thus, molecular markers are necessary to evaluate the genetic effects. Within this context, a census of the species was conducted in a swampy forest fragment, with four height classes being established for genetic analysis. The alloenzymatic markers revealed a total of 11 polymorphic loci with a mean number of 2.0 alleles in each locus it was not observed the loss or alleles fixation. The observed heterozigosity was larger than that expected for Classes II and IV, evidencing heterozygote excess. Classes I and III presented homozygote excess, the value being non significant for Class I. The genetic diversity values found were considered high compared to other tree species. Thus, the occurrence of mutations and the incorporation of new alleles in the population are high, besides increasing the recombination number and multiple paternities in the progenies. Overall, the analysis of the spatial distribution of the genotypes was random for most classes analyzed, except for Class I, where the individuals close to a 10m distance presented family structure. The high genetic diversity of this species and absence of spatial structuring of the genotypes in most of the classes analyzed should be considered for conservation planning of this area.

Isoenzyme; cohorts; temporal structure


Sociedade de Investigações Florestais Universidade Federal de Viçosa, CEP: 36570-900 - Viçosa - Minas Gerais - Brazil, Tel: (55 31) 3612-3959 - Viçosa - MG - Brazil
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